Diffusion tensor imaging in the courtroom: Distinction between scientific specificity and legally admissible evidence

Abstract

Interest and uptake of science and medicine peer-reviewed literature by readers outside of a paper's topical subject, field or even discipline is ever-expanding. While the application of knowledge from one field or discipline to others can stimulate innovative solutions to problems facing modern society, it is also fraught with danger for misuse. In the practice of law in the United States, academic papers are submitted to the courts as evidence in personal injury litigation from both the plaintiff (complainant) and defendant. Such transcendence of an academic publication over disciplinary boundaries is immediately met with the challenge of application by a group that inherently lacks in-depth knowledge on the scientific method, the practice of evidence-based medicine, or the publication process as a structured and internationally synthesized process involving peer review and guided by ethical standards and norms. A modern-day example of this is the ongoing conflict between the sensitivity of diffusion tensor imaging (DTI) and the legal standards for admissibility of evidence in litigation cases of mild traumatic brain injury (mTBI). In this review, we amalgamate the peer-reviewed research on DTI in mTBI with the court's rationale underlying decisions to admit or exclude evidence of DTI abnormalities to support claims of brain injury. We found that the papers which are critical of the use of DTI in the courtroom reflect a primary misunderstanding about how diagnostic biomarkers differ legally from relevant and admissible evidence. The clinical use of DTI to identify white matter abnormalities in the brain at the chronic stage is a valid methodology both clinically as well as forensically, contributes data that may or may not corroborate the existence of white matter damage, and should be admitted into evidence in personal injury trials if supported by a clinician. We also delve into an aspect of science publication and peer review that can be manipulated by scientists and clinicians to publish an opinion piece and misrepresent it as an unbiased, evidence-based, systematic research article in court cases, the decisions of which establish precedence for future cases and have implications on future legislation that will impact the lives of every citizen and erode the integrity of science and medicine practitioners.

Keywords: Diffuse axonal injury; Ethics; Litigation; Magnetic resonance imaging; Medical jurisprudence; Medicolegal; Mild brain injury; Neuroimaging; Peer review; Publishing.

Figure 1

Imaging evidence of a traumatic brain injury in a representative patient. A: Bright spot on T2-weighted images near the gray-white junction, consistent with traumatic axonal injury (orange arrow); B: Close-up of lesion shown in Panel A (orange arrow); C: Microhemorrhage near the gray-white junction shown on a microhemorrhage-sensitive magnetic resonance image (orange arrow); D: Gaps in the normally continuous distribution of tracts that pass through the corpus callosum; E: Diffusion tensor imaging (DTI) tractography of the relatively normal right fronto-occipital fasciculus; F: DTI tractography of the left fronto-occipital fasciculus showing decreased tracts compared to the right side shown in Panel E.